WEST CHESTER, Pa. — Paul Ryan came to the normally electorally essential Philadelphia suburbs Tuesday to talk to a crowd of more than 3,000, his first time in the state since joining the Republican ticket.

But unlike other major battleground states, where the Romney team has saturated the airwaves with ads, Mitt Romney hasn’t run a single ad in the Keystone State since the start of the general election.

Pennsylvania, once a perennial swing state and one that was hotly contested four years ago, has gotten little attention from the candidates this year. And yet, despite polls showing President Barack Obama ahead here and the fact that no Republican presidential candidate has won the state since 1988, Romney staffers say they still think the state is competitive — and observers say the race could very quickly tighten between now and November.

But right now, the Keystone State is surprisingly bereft of political attention. And that lack of love from the top of the ticket could have a trickle-down effect on Republicans running down-ballot.

So far, the state has seen far less personal attention from the candidates than it’s used to: Romney campaigned in Irwin, Pa., a Pittsburgh suburb, in mid-July, and was here for a June bus tour. Obama came to Pittsburgh in early July, and Joe Biden recently visited the Pittsburgh area and Philadelphia. But compared with other major battleground states, like Ohio or Florida, the candidates are virtually ignoring Pennsylvanians.

“What we haven’t seen a lot lately is visits to the state by either candidate,” said G. Terry Madonna, who conducts the Franklin & Marshall polls in the state. “There isn’t any doubt that the advertising and TV we saw four years ago is missing.”

Back in 2008, McCain poured resources into Pennsylvania, only to lose it to Obama by 10 points. And this year, when Obama has a modest lead in most polling from the state — an F&M poll out last week gave Obama a 6-point advantage for example — observers say the Romney campaign is making the kind of political calculation McCain didn’t.

“The Romney campaign itself has put forth minimal effort in Pennsylvania, especially compared to what they’ve done in other swing states,” said Chris Borick, who does polling for Muhlenberg College. “[That leads] one to conclude that as a battleground, it’s a secondary goal for them right now.”

That lack of attention, he said, could manifest itself in close down-ballot races as well.

“It does not look like we will have a wave election as we had during the last three cycles, so little things could matter like visits and energizing folks,” Madonna said.

In many respects, Obama looks poised to win the state again: the Democrat won by a full 10 points in 2008, a much wider margin than other recent Democratic candidates. Democrats have a registration advantage of more than a million voters (out of the state’s total 8 million). And despite the fact that the state has been competitive in most elections, it hasn’t gone to a Republican candidate in 24 years.

The Obama campaign originally went up on the air with much larger TV buys in May and June after Romney became the presumptive GOP nominee, but scaled their buys back and focused more on radio as Romney’s campaign stayed out of the state. Outside spending, though, has kept pace in Pennsylvania: super PACs allied with both sides, Priorities USA and Restore Our Future, have been running ads there, as well as the GOP-aligned groups Crossroads GPS and Americans for Prosperity.

“The super PAC spending has probably served to keep the race competitive and to give the Romney campaign an opportunity to use its resources elsewhere — and to really see if without doing much, Pennsylvania will remain in range for them,” Borick said.

Despite the Romney campaign’s lack of a presence on the Keystone state airwaves, a handful of factors — a new voter ID law and a GOP-heavy lineup of elected officials that rode the Republican wave into office in 2010, not to mention high Obama’s disapproval rating here and voters’ low opinions of his handling of the economy — make Republicans in the state optimistic about Romney and Ryan’s chances there.

“Barring a war in the Middle East, or some other cataclysmic thing, I believe that Mitt Romney and Paul Ryan will be elected from Pennsylvania,” Pennsylvania GOP chairman Rob Gleason said.

And Ryan’s visit to West Chester underscores the Romney campaign’s investment in the idea that there’s still an opening to turn the state red — and that the path to do so runs right through suburban Philadelphia.

Traditionally, any candidate hoping to win a statewide race in Pennsylvania needs to win the four collar counties around Philadelphia: Bucks, Delaware, Montgomery and Chester, where Ryan campaigned Tuesday afternoon, plus areas of suburban Pittsburgh in southwestern Pennsylvania.

The Republican ticket also hopes to appeal to small-town rural voters that supported Hillary Clinton in the 2008 Democratic primary. On Tuesday, Ryan hoped to appeal to these voters when he revived Obama’s remarks from four years ago when he, as a “Catholic deer hunter,” he said he was “happy to be clinging to my guns and religion.”

A Franklin & Marshall poll found Obama leading Romney in southeastern Philadelphia — where Tuesday’s event was held — by 9 points, 47 percent to 38 percent.

The area is a major focus of Romney’s ground game here: of 20 total victory offices in the state so far, six are in those four counties alone — two each in Chester and Montgomery, and one in Bucks and Delaware — plus another office in Philadelphia and one in the nearby Lehigh Valley.

“Gov. [Ed] Rendell, who won two statewide races here, has said himself that southeastern Pennsylvania is an area that would play very well for Gov. Romney and his business experience and his record on job creation,” said Billy Pitman, the spokesman for the RNC’s Pennsylvania victory operation.

The Philly suburbs are a place where observers in the state say Romney could have a real opportunity to make gains, given his private-sector resume.

“Especially in places like the Philly suburbs, I still contend that Mitt Romney has a chance to make significant gains over John McCain in 2008 — largely because many of those voters that have started out for Barack Obama may not be completely sold that he deserves a second term, and that Mitt Romney is in some ways an option that they might explore because of his business credentials,” Borick said.

Still, in the wake of the now-national flap over Missouri Rep. Todd Akin’s comments about “legitimate” rape last weekend, moderate and independent suburban voters — especially women — may be turned off if Romney and Ryan are unable to separate themselves from the Missouri pol.

Borick said one of the main reasons Romney has such opportunity for growth in the Philadelphia collar counties is precisely because he’s not viewed as too conservative on social issues.

“He’s not as threatening to [suburban voters] on some of the social issues that have pushed them from the Republican Party,” he said. “He’s not [former Pennsylvania senator] Rick Santorum.”

The other issue that’s taken center stage since Ryan joined the ticket, Medicare, could make things difficult for Romney and Ryan here too: Pennsylvania has a significant population of elderly voters.

Still, how both campaigns ultimately plan to handle the Keystone State this fall — and just how much the race here could tighten — remains to be seen.

Romney’s lack of TV investment in Pennsylvania is partially strategic and could change: most of the millions of dollars in Romney’s war chest can’t be accessed until after the Republican convention in Tampa next week, when he will officially become the party’s nominee.

“Does the Romney campaign just want to keep [Obama] down here, keep Obama spending money, keep him here, or does he want to really invest some time and energy in this state? That remains really undecided at this point, I don’t think anyone knows for sure,” Madonna said.